The present invention relates to light filters and more particularly to a solar blind ultraviolet (UV) filter.
Solar blind UV filters provide a sharp attentuation in a short spectrum period to give a black background for the event being viewed and eventually detected and is employed to improve the performance of light detectors having unsuitable operating characteristics.
Solar blind UV filters in the prior art use a combination of doped glasses, crystals and thin films to achieve transmission in the 0.25 to 0.285 micron region. These prior art devices have low peak transmission in the band of interest and out-of-band light leaks which required the use of multilayer dielectric films to correct. The use of these films degraded the off axis performance of the filters.